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Please see the attached image. I built this stand for my 180 gallon aquarium and I'm a little concerned with the gap between the stand and tank. I've read that as long as all four corners are touching (which they are) then it should be fine but I wanted to get more opinions. It is approximately a 1/16 to 1/8 inch gap. Im concerned it will cause the glass to stress and crack. Also, any thoughts on putting foam between the tank and stand?

U definitely want more then just the 4 corners in contact with the stand. U really want the entire bottom trim in contact with the stand. I may could live with 1/16” or less but if it is 1/8” I would fix it. It is usually the stand that is a issue but in your pic it looks like it may be the tank trim, but it could just be the pic. If a section of the trim isn’t in contact with the stand it could definitely cause stress on the glass.

It is usually the stand that is a issue but in your pic it looks like it may be the tank trim

I see what you mean in the photo but I'm assuming that's just the lens effect of strong light bleeding through a really narrow gap.

Regarding the comments to fill the tank and see if it goes away - personally, I don't think that's good practice. If filling it makes it go away, that basically means you're introducing stress into the structure to the point that it's deforming. And that can lead to disaster down the road. Having a tank level differently after filling because it's on carpet, or some other trivial issue, is one thing - but having the contact patch between the tank and stand change under stress means you're deforming something. If it's the wood in the stand that is deforming, it may not be an issue for the wood itself, but in order to cause that deformation you're basically using the tank to point load the stand until it moves, which means the tank is under stress it wasn't designed for. Yes, they may now fully touch when full, but that doesn't mean the weight is actually being distributed evenly, as it should be.

A tank and stand that are built straight and true should not change their relationship to each other when full vs empty and should sit correctly with no weight on the tank.

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Inconveniencing marine life since 1992

"It is my personal belief that reef aquaria should be thriving communities of biodiversity, representative of their wild counterparts, and not merely collections of pretty specimens growing on tidy clean rock shelves covered in purple coralline algae." (Eric Borneman)